(a) [2 points] Build a 2D range tree (including all associated structures) for the point set in figure (a). Use the lower median to split the set of points. (Note: Fill in the split values in all internal nodes and add the point labels to all leaves. A starting setup is supplied in the template of this week.) (b) [1 points] Consider querying the range tree from (a) with the query rectangle shown in figure (b). Highlight the two leaves found by 2DRANGEQUERY that are inside the query rectangle. (Make sure you highlight the correct leaves containing P6 and 27.) P8 8 8 7 ??? 7 81 P6 P6 6 6 5 B 5 B? 4 3 83 4. 3 2 1 82 23 25 34 2 1 84 0 0 0 0 1 2 3 4 5 8 1 2 3 6 7 8 (a) (b)